ABSTRACT
In recent times, light gauge cold-formed steel sections have been used extensively as primary load bearing structural components. These members are susceptible to various buckling modes such as local and distortional buckling, but their buckling performance under fire conditions is not well understood. Therefore numerical and experimental analyses were used to investigate the distortional buckling behaviour of light gauge low (G250) and high (G550) strength cold-formed steel compression members with two different cross sections and various thicknesses (0.6 to 0.95 mm) under varying temperatures (20 to 800° C). Degradation of mechanical properties with temperature was included in the numerical analyses. The numerical analysis results were then compared with experimental results to validate the numerical model. The validated numerical models were used to investigate the distortional buckling characteristics and the suitability of currently available design methods for fire conditions. This paper presents the details of this investigation and the results.
